Conduit mold



Allg. 12 1924.

T. DE LA MARE CONDUIT MOLD Mm. SN. @l WN d Wwwww/m @w mm Pil flll ,mklr will km mw RM. xw n jl We@ Aug., 12 1924. 1,505,004

T. DE LA MARE CONDUIT MOLD Filed Sept. 20.. 1920` 2 Sheets-Sheet 2 ATTO R N EY WWQJZaWI'QNVENTOR,

BY o I] Patented Aug. 12, 1924.

UNITED sTATEs PATENT OFFICE.

THOMAS :on LA MARTE;J or TooELn, UTAH.

CONDUIT MOLD.

Application iled September 20, 1920. Serial No. 411,642.

ented by me November 24, 1914, No. 1,118,-`

A more specific object is to provide means whereby a single conduit mold ymay be used to make conduits of at least two different sizes. y

Another object is to provide improved means for expanding and contracting the shell or drum of the apparatus.

A further object is to provide means for forming a bell or enlarged joint between adjoining sections of the conduit.

@ther objects are to provide a conduit mold whose parts are readily detachable, making it easy to ship, and which are easily assembled in the field. y

Still another object is to provide means for keeping the concrete from getting under the cap, for preventing sticking ofthe concrete to the cap and drum, and for making a good surface on the inside of the conduit on the upper part thereof.

The invention will be b est understood from a. consideration of the following detailed description taken in connection with the accompanying drawing forming part of this specification, with the understanding, however, that the invention is not confined to any strict conformity with the showing in the drawing, but may be changed and modified so long as such changes and modiications mark no material departure from the salient features of the invention as eX- pressedin the appended claims.

In the drawing i Figs. 1 and 1a taken together show a verti cal longitudinal sectional view of the im proved apparat-us in use with the shell or drum shown expanded.

Fig. 2 is a View partly in section and partly in plan of that portion of the conduit and .apparatus disclosed in Fig. 1.

Fig. 3 1s an end elevation of the conduit and mold, the view being taken from the enlarged or working end.

Fig. 4t is a vertical transverse cross-seo.

tion.

Fig. 5 is a detail showing the arms connected with a reversed block on the pull rod so that the mold may be used to make a smaller conduit. i

The main body yof the conduit mold is formed from a pair of arcuate shells 6,-

each less than a semi circumference and each having inturned flanges 7v along their upper edges, which flanges are always maintained spaced apart as indicated particu larly in Figs. 3 and `4. The other edges of the shells 6 have inturned flanges 8 narrower than the flanges 7. VAn auxiliary section 9 is employed which is arcuate and of the same curvature as the sections 6, when the mold is to be use-d for thelargest size of pipe for which it is designed. The auxiliary section 9 has its longitudinal edges terminating in inturned flanges 10 corresponding to the flanges 8l Then the auxiliary section 9 is used with the shell sec tions 6, the fianges 8 and 10 will be abutted and joined `by bolts or similar elements. lVhen the apparatus is employed for making a smaller size of pipe, the auxiliary section 9 willbe removed and the two flanges 8 will be joined together by bolts or the like. Whether the particular shell is used for making relatively small or large sizes of pipe or conduit, it will be closed except on its upper side where t-he flanges 7 are normally spaced apart a short distance. The space between the flanges 7 is covered by a cap plate 11 which is arcuate transversely and extends the entire length of the apparatus. At intervals along the under face of the cap plate 11, inturned bends 12 are provided which prevent the cap plate from sliding off the top o-f the shell before the con-4 crete has been poured.

At the forward or working end of the shell, an extension band 13 is provided (see Figs. 1 and 3), which band makes Vthe conduit a trifle larger at its end to permit ready withdrawal of the inoldafter the concrete has set. This extension band is permanently secured in any desirable way upon the outside of the shell section and is split or broken at the joint between the sections, so that whether the auxiliary section 9 is employed or is removed, a slight enlargement in the passageway of the conduit will be formed at the forward end of the apparatus. The extension band 13 extends only about two-thirds of the way around the shell, as seen in Fig. 3.

In the embodiment of the invention illustrated in Figs. l and la, a construction suitable for making'twenty feet of pipe is shown, which employs two molds each ten feet long and joined together at' their ends. Each mold has two toggles or expansion means to cause the sections yof the shell to separate or close together when desired. Operating means is provided at the forward end of the apparatus for causing all the toggles to work together. Thetwo molds are shown as connected by a coupling plate 14 which is an annular member secured within twoalined molds at their abutted ends. Then the apparatus is shipped, the molds will be separated, butin use in the field the molds will be permanently joined together so that twenty feet of lO-inch or 12-inch conduit maybe laid ata time.

The size and form of the interior of the conduit isdetermined bythat portion of the mold including the shells and the expansion means. The lower part of the conduit is v laid in the trench rand may assume the size and form ofthe excavation. The outer and upper part ofv the conduit is shaped by a pair of side forms 15 in conjunction with a hopper member. See Figs. 3 and 4L. The side forms 15 are arcuate transversely and extend the length 'of the mold. The hopper comprises a pair of arcuate sections 16 whose curvature is that of the side forms 15 having upstanding flanges 17 and handles 18 adjoining the iianges and holding the parts ofthe hopper together. The flanges 17 are spaced apart as best shown in Fig. 2 to provide a wide mouth for receiving the concrete as it is poured from the mixer. The side form has a raised and the forward end of the hopper member has a raised offset 19, these two offset portions being arcuate transversely, as shown in Fig. 3, and providing a bell or enlargement at the joint between two secv'tions of the conduit. This bell is formed only on the upper half of the conduit, since the side forms and hopper extend for 'only approximately half the circumference of the conduit. At the top of the offset portion 19 a slot 22 is described.

With the present apparatus, a cloth 21 preferably canvas or the like is doubled and laid over the cap plate 11 extending the enprovided for a purpose to be tire length of the mold. The fold of the cloth is indicated at 21 (Fig. 1). This cloth should have a width substantially equal to one-third of the circumference of the shell or drum, and when properly positioned has its forward end extending to the offset 19. The purpose of using this cloth is fourfold: first, to keep the concrete from getting under the cap; second, to prevent the oil coated on the outside of the shell from being swept off by the pouring of the concrete with resultant sticking of the concrete to the cap plate and drum; third, to permit rapid work with liquid or sloppy concrete,so that as soon as one section has set the mold may be withdrawn and immediately used with another section; and fourth, to make a good surface on the u per part of the conduit lon the inside thereoil W'hen the concrete 2O has been oured in through the hopper member an has set, the shell is contracted and withdrawn, leaving the cloth sticking to the inside of the conduit. Because the cloth has been doubled, however, one half of it will be free from the concrete and it will then be easy to take hold of the end of this free half and peel the cloth off the inside of the conduit, whereupon it may be used over again for the adjoining section of the conduit.

The means for expanding and contracting. the shell sections will now be described.` Each mold has a pull rod 23 located axially of the shells. There two molds are joined together, as in making 20 ft. of pipe, the two pull rods 23 will be coupled by means lof a sleeve 24; of any convenient form so that the toggles in each mold will act simulta` -neously. The forward end of the pull rod 23 is screw-threaded as indicated at 25 to receive a nut 26 in turn pivotally connected with a pull strap 27. The other end of tho pull strap 27 has an angularly-beut end 32 (Fig. 1) connected by a bolt or the like 33 with an operating wheel 30. This Ioperating wheel turns upon an axis 29 mounted hctween a pair of brackets 28 secured in any desirable way to the inside of the shell. The operating wheel 3() is provided with a plurality ofY holes 34 in a circular series. The wheel also carries spokes 31 on its periphery so shaped as to be readily received within one end of a turning tool 40. The element 33 is passed through a selected one of the holes 34 in the wheel.

At suitable intervals along the pull rod 23 toggle means are provided for connecting the rod with the inside of the shell so that longitudinal movement of the rod is translated into expansion or contraction of the shell. Each toggle includes a pair of set collars 35 secured upon the pull rod. Between each pair of set collars a number of blocks 3G are held. Each block 36 has a squared end and a rounded end and is so mounted that it may turn about the pull rod 23 as an axis. A pair of straps 37 is se' cured to the sides of each block 36, each pair of straps comprising a toggle arm. The outer arms of the straps 37 approach each other and are joined with an angle piece 39 mounted upon the inside yof the shell at a convenient point. Preferably there are four toggle arms for a mold making conduits as large as ten or twelve inches. For small molds as few as two armsmay be employed and with very large molds the number of arms will be increased as desired.

When the auxiliary section 9 is employed one of the blocks 36 is joined to a pair of diverging legs 38 each connected with the joined flanges 8, 10, as shown in Fig. 1. If the same apparatus is used for building a smallell conduit the legs 38 will be disconnected or even removed from'the apparatus. For this smaller pipe, each block 36 will be turned about the rod 23 or put into the reverse position as illustrated in Fig. 5 and connected with the toggle arms in this position. Thus, the effective length of each toggle arm is decreased, whereby the expansion and contraction of the apparatus is changed to correspond with the decreased size of conduit to be made.

The drawing illustrates the toggle arms as being disposed at right angles to the pull rod, in which position the shell is expanded to its utmost extent. Then the parts are in this position, the pull strap has its bent end 32 pressing against the axis 29 of the pull wheel. If, however, it is desired to release the mold from the conduit so as to withdraw the same. preparatory to building another section, the operator will place atool 40 over one of the spokes 31 and will pull downward on the tool to cause the wheel to rotate in a clockwise direction as viewed in Fig. 1. This will first cause the pull rod to move to the left; then as the wheel is turned further the rod is moved to the right and the pull strap being connected to the wheel follows the same around until the toggles are in releasing position, when the shell sections contract. The inturned flanges 7 will now nearly meet each other without, however, pinching the bends 12 or preventing the ready removal of the cap plate 11. In turning the pull wheel, it is desirable to have as much room as possible in which to work with the lever arm 10. For this reason, the otlset section of the hopper 19 is cut away as at 22. This cut-away section or slot 22 permits the turning tool 40 to be introduced from above and then moved downwardly until it strikes the bottom of the trench. When the limit of movement of the lever arm is reached, a pin will be inserted within that hole 33 nearest the appropriate edge of bracket 28 so that turning back of the wheel will not be permitted while the operator gets anew hold with his lever arm; The provision of the nut 26 on the screw-threaded section 25 of the pull rod and also the connection between the pull strap and the pull wheel enables the operator to adjust the parts so that the maximum expansion of the shell may be made.

By properly using the apparatus of the present invention, I Vhave found it feasible with a 20-foot mold to lay four sections of pipe in a working day; that is, to build eighty-feet of concrete pipe twelve inches in diameter or greater during eight hours. The use of a cloth as described is largely instrumental in bringing about this rapid operation.

It will be noted that the pull strap 27 locks the expansion means in approximately the position of maximum expansion, as indicated in Fig. 1, because of the engagement of end 32 with the pivot 29. Hence it is not necessary to use pins passing through the holes 34 to lock the pull wheel when the toggles have spread the shell completely. It will also be noted that the bell or enlargement strengtlr ens the conduit where the inner passage thereof is enlarged by the extension band 13 and where conduit sections join each other. The brackets 28 are shown as secured to the removable section 9. They may vbe fixed upon the shells 6, to the flanges 10, or at other convenient points, when the section 9 is not used.

What is claimed is 1. Apparat-us for molding a continuous concrete conduit in a trenchcomprising an expansible shell, said shell being composed of a plurality of arcuate sections separated at the top to permit expansion and contraction, an arcuate cap plate extending the length of the shell and covering the space between the shell sections, and a flexible covering for the cap plate to prevent the concrete from sticking thereto.

2. Apparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, said shell being composed of a plurality of arcuate sections separated at the top to permit expansion and contraction, an arcuate cap plate extending the length of the shell and covering the space between the shell sections, and a textile covering placed upon the upper side of the shell and completely covering the cap plate and extending the entire length of the shell, said covering being doubled to present two thicknesses between the concrete and shell.

3. Apparatus for molding a continuous 0concrete conduit in a trench comprising an expansible shell, means within the shell for expanding or contracting the same, and an extension band secured to the forward end of the shell on the outside thereof, said band extending along the sides and bottom of the shell but not along the top, said extension band enlarging the passage of the conduit whereby ready withdrawal of the shell after the concrete has set is made possible.

4. Apparatus for molding a continuous concrete conduit -in a trench comprising an expa'nsible shell, means within the shell for expanding or contracting the same, an extension band secured to the forward end ofthe shell on the outside thereof, said band extending along the sides and bottom of the shell but not along the top, said extension band enlarging the passage of the conduit whereby ready withdrawal of the shell after the concrete has set is niade possible, and means forforming the upper part of the conduit in cooperation with said shell, said means providing an enlargement or bell in the conduit at the forward end of the shell extending around the top and sides of the conduit. i

5. Apparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, means for expanding and contracting the shell operable at one end thereof, a hopper member arcuate transversely and having an offset at the working end of the shell, and side forms arcuate transversely and also offset, the olfsets forming a bell or enlargement 'about half way around the conduit on the upper and outerportion thereof at the end of every section molded by' the apparatus.

6. Apparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, said shell being composed of a plurality of arcuate sections joined together except; at the top and there separated, in'turned' flanges on each shell section bordering the` spacey where the sections are separated, a cap plate curved transversely to lit upon the top of the shell and cover said space, inturned bends provided on the under sides of the cap plate and extending into the space between the flanges to hold the cap plate on the shell.

7. Apparatus for molding a. continuous concrete conduit in a trench comprising an expansible shell, said she-ll being composed of a plurality of arcuate sections joined togetherxexcept at thetop and there separated, inturned flanges on each shell section bordering the.V space where the sections are separated, a cap plate curved transversely to t upon the top of t-he shell and cover said space, inturned bends provided on the under sides of the cap plate and extending into the space between the flanges -to hold the cap plate on the shell, and means for covering` the joints between the cap plate and shell whereby concrete is prevented from getting in between 'these two parts.

.8. Apparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, and means forexpanding and'contracting said shell, said means comprising a pull red extending axially of the shell, a plurality of toggle arms secured against longitudinal movement on the pull rod and extending substantially radially of the shell in planes lnogressively spaced along the pull rod, and lixed at their outer ends to the inside of the shell, and means for moving the pull'rod, said means being self-locking when the shell is expanded to approximately its maxin'mm.

9. Apparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, and means for expanding and contracting said shell, said means comprising a pull rod extending axially of the shell, a plurality ot toggle arms secured against longitudinal movement on the pull rod and extending substantially radially of the shell and fixed at their outer ends to the inside of the shell, means for moving the pull rod, said means being self-locking when the shell is expanded to approximately its maxinnun, and means for positively locking the pull rod moving means whereby the shell may be maintained interu'icdiate the expanded and contracted states.

10. Apparatus for molding a` continuous concrete conduit in a trench comprising a circular expansible shell, means for varyin'fr the circumferential dimensions of the she l tO provide a substantially circular shell of a decreased diameter, and means for expanding and contracting the shell whatever its circumference may he, said n'ieans comprising a pull rod, a pluralityY of toggle arms in sets, each set being lixed against longitudinal movement on the pull rod and also fixed on the shell, and `separate meansI whereby the ell'ective operating length ol" the tog gle arms may be decreased lo conform to the changed diameter of the circular shell.

1l. Apparatus for moldingl a continuous concrete conduit in a. trench coml'irisiug an expansible shell, and means for expanding and contracting the shell, .said means comprising a pull rod, a plurality ot toggle arms lived to the shell and pull rod in planes progressively spaced along said rod. a pull strap adjustably secured to one end of the pull rod, and a wheel adjustably connected to the pull strap Vfor reciprocating the rod.

l2. Apparatus `tor molding a continuous concrete conduit in a trench comprising an cxpansible shell, and means tor expanding and contracting the shell, said means comprising a pull rod, a plurality of toggle arms fixed to the shell and pull rod, u pull strap adj'ustably secured to one end of the pull rod, and a wheel adjustably connected to the pull strap for reciprocating the rod, said wheel having a plurality ot spokes projecting from its rim adapted to be engaged by the end of a lever arm.

13. vApparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, and means i'or expanding and contracting the shell, said means comprising a pull rod, a plurality oit toggle arms :tixed to the shell and pull rod, a pull strap secured to one end ot the pull rod, said pull strap having a bent end remote 'from the connection with the pull rod, and a Wheel connected to the pull strap for reciprocating the rod, said Wheel having a pivot against which the bent end of the pull strap engages to loci; the parts when the shell has been expanded.

14. Apparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, a hopper member having an otlset at one end, a slot or cutaway portion in the oliset end, and means for expanding and contracting the shell, said means comprising a pull rod, a plurality of toggle arms fixed to the shell and pull rod, a pull strap secured to one end oit the pull rod, and a Wheel connected to Ythe pull strap for reciprocating the rod, said Wheel having a plurality of spolres projecting from its rim adapted to be engaged by the end of a lever arm, said slot permitting` movement of the lever arm up to a vertical position.

15. Apparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, a pull rod extending longitudinally and axially of the shell, a plurality of toggle arms fixed at their outer ends to the inside Wall of the shell, blocks connecting the toggle arms at their inner ends to the pull rod, said toggle arms being arranged in sets, collars on the pull rod holding the blocks of each set against movement along the pull rod, each block being turnable and slidable on the pull rod and being eccentrically mounted thereon, Whereby the blocks When reversed With respect to their arms shorten the ehfective length ot said arms.

16. Apparatus :tor molding a continuous concrete conduit in a trench comprising a circular expansion shell, said shell being composed of a plurality ot arcuate sections, one of said sections being removable to reduce the circumference of the shell and pro- 'Je a circular shell oi: less diameter, and

means for causing expansion and contraction of the shell irrespective of the presence or absence of the removable shell section.

1T. Apparatus for molding a continuous concrete conduit in a trench comprising a circular expansion shell, said shell being composed of a plurality of arcuate sections, one of said sections being removable to rev duce the circumference of the shell and provide a circular shell of less diameter, means for causing expansion and contraction of the shell irrespective of the presence or absence of the removable shell section, said means comprising a rod extending longitudinally of the shell, and a plurality ot' toggle arms connected to the rod and shell and supporting the rod in the longitudinal axis of the shell.

18. Apparatus for molding a continuous concrete conduit in a trench comprising an expansible shell, and means for expanding and contracting the shell, said means comprising a pull rod, a plurality of toggle arms iixed to the shell and pull rod, a pull strap adjustably secured to one end of the pull rod, and a Wheel adjustably connected to the pull strap for reciprocating the rod, a braclret secured to the shell and supporting the Wheel, the Wheel having a plurality of holes arranged in a circle for receiving the connecting element ot the pull strap and for receiving pins to act as stops When the shell is being expanded.

19. Apparatus for molding continuous concrete conduits in a trench comprising a circular expansible shell, means for Varying the circumferential dimensions of thev shell to provide a circular shell of a different diameter, means comprising a pull rod, and a plurality of toggle arms in sets adapted to expand and contract the shell, and a reversible means for pivoting the toggles on the pull rod, said means when in reversed position adapted to change the pivotal pointo'f the toggles whereby the effective length of the toggle arms may be varied to contorni to the changing diameter of the circular shell;

In testimony that I claim the foregoing as my own, I have hereto aflixed my signature.

THOMAS DE LA MARE. 

